v3.19.3.a.u2
Property, Plant And Equipment (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 333,538 $ 330,690  
Accumulated depreciation and amortization 203,410 199,217  
Property, plant and equipment - net 130,128 131,473 $ 125,222
Land [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 2,651 $ 2,714  
Land [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 0 years 0 years  
Land [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 0 years 0 years  
Buildings and Improvements [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 38,924 $ 38,013  
Buildings and Improvements [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 2 years 2 years  
Buildings and Improvements [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 44 years 44 years  
Central Office Equipment [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost [1] $ 96,061 $ 95,173  
Central Office Equipment [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 3 years 3 years  
Central Office Equipment [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 10 years 10 years  
Cable, Wiring And Conduit [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 72,042 $ 73,397  
Cable, Wiring And Conduit [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 15 years 15 years  
Cable, Wiring And Conduit [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 50 years 50 years  
Satellites [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 2,489 $ 2,961  
Satellites [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 14 years 14 years  
Satellites [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 17 years 17 years  
Other Equipment [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 94,951 $ 93,782  
Other Equipment [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 3 years 3 years  
Other Equipment [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 20 years 20 years  
Software [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 22,244 $ 19,124  
Software [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 3 years 3 years  
Software [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 7 years 7 years  
Under Construction [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, at cost $ 4,176 $ 5,526  
Under Construction [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 0 years 0 years  
Under Construction [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Property, plant and equipment, useful life 0 years 0 years  
[1] Includes certain network software.